This invention relates to a depth of cut adjustment mechanism for a portable electric routing tool and, more particularly, to an arrangement for clamping a depth of cut adjustment split ring to such tool.
The particular router with which the present invention finds utility includes a motor housing having an external cylindrical portion, with a cutting tool mounted at one end of the motor housing to the shaft of the motor supported within the motor housing. The cylindrical portion has a first longitudinal region with a substantially smooth surface and a second longitudinal region with an external screw thread. The router also includes a base having a cylindrical bore for slidably receiving therein the first longitudinal region of the motor housing cylindrical portion. The depth of cut adjustment mechanism includes an adjustment ring which is split with an opening between two opposed ends. The adjustment ring engages the screw thread on the motor housing and rotationally engages the base, whereby rotation of the adjustment ring effects relative longitudinal motion between the motor housing and the base so that the distance which the cutting tool projects beyond the base may be varied. It is an object of this invention to provide an arrangement for releasably securing the adjustment ring to the motor housing and the base so as to maintain the position of the base relative the motor housing.
Prior router depth of cut adjustment mechanisms utilizing a split adjustment ring have included projections on opposite sides of the split which are squeezed together to effect a clamping action by means of a threaded member arranged generally tangential to the ring. These arrangements are not entirely satisfactory because, for example, there is insufficient room for manipulating the threaded member. It is therefore another object of this invention to provide a more effective split ring clamping arrangement.